Critical temperatures and pressures for dilute supercritical fluid-entrainer systems are imperative for the design of efficient and environmentally conscious separation processes. In this study, the constant volume, visual method is used to measure the critical point of CO2 + acetone, CO2 + toluene, CO2 + propan-2-ol, CO2 + methylene chloride, CO2 + benzene, and ethane + benzene mixtures. The dilute entrainer concentration region is emphasized. The estimated experimental error for the critical temperature and pressure measurements is 10.5 K and +/-0.7 bar, respectively. Molar volumes are presented for all systems studied.